Hmmm... 4895. I have been thinking about this for a couple of days now, and since I don't reload rifle much maybe you can school me on this. My first thoughts are that what matters for a gas operated rifle is the pressure. The closer you get to "optimal pressure" for the action, but still safe for the lead (or coated) bullet is what would seem to me to be ideal. So something that produces what would be "minimal operating pressure" for your gun, but still keeps the bullet at or under 2000fps is what you're looking for. Like you mentioned, to do that you might have to go with a heavier bullet using a rifle powder. My first reaction was to think about powders like Lil' Gun or H110 for the 165grn if they are bulky enough without "fillers", but seeing this is a gas gun, fillers might be a no go and I don't think ANY of the slow pistol powders will have enough bulk for a 30-06 case, and even the "fast" rifle powders might not light up at reduced pressure so I am sort of confused about the 4895 which is not really that fast a powder (maybe in this case size?). I am guessing you think it is the fastest powder you can use that has sufficient bulk for the case. Is my thinking correct? I trust your experience with rifles more than my own on this so I'm really curious about how this comes out. This will be a fascinating experiment.